Move core control from out-of-tree module into the kernel proper.
Core control monitors load on CPUs and controls how many CPUs are
available for the system to use at any point in time. This can help save
power. Core control can be configured through sysfs interface.
Change-Id: Ia78e701468ea3828195c2a15c9cf9fafd099804a
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Remove the core control helper code since this is not needed anymore
with subsequent patches that moves core control into the kernel.
Change-Id: I62acddeb707fc7d5626580166b3466e63f45fd89
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Core control helper is not needed anymore with subsequent patches
that moves core control into the kernel.
Change-Id: I2c62af441fb9e5ba9f29719853a63e4c8f2d031b
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Timers should not be queued on isolated cpus. Instead try to find
other cpus to queue timer on.
Change-Id: I5d849dfd29aa5bb594454473768d7db1da258028
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Ensure perf events does not wake up idle cores when core is isolated.
Change-Id: Ifefb2f1cf6c24af7bc46fc62797955b8c8ad5815
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Set long latency requirement for isolated cores to ensure LPM logic will
select a deep sleep state.
Change-Id: I83e9fbb800df259616a145d311b50627dc42a5ff
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Ensure vmstat updates do not run on isolated cpus.
Change-Id: I401de0b52fa6d20573187265ee56edd543b1419e
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Prohibit setting the affinity of an IRQ to an isolated core.
Change-Id: I7b50778615541a64f9956573757c7f28748c4f69
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Add a new per-cpu node to control isolation of CPU.
Usage:
echo 1 > isolate - Isolate the core
echo 0 > isolate - Unisolate the core
Change-Id: I6a13e8dda99130ca794e5b6f51600f4c57a3e921
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Add tracepoint to capture the cpu isolation event including KPI for
time it took to isolate.
Change-Id: If2d30000f068afc50db953940f4636ef6a089b24
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
This adds cpu isolation APIs to the scheduler to isolate and unisolate
CPUs. Isolating and unisolating a CPU can be used in place of hotplug.
Isolating and unisolating a CPU is faster than hotplug and can thus be
used to optimize the performance and power of multi-core CPUs.
Isolating works by migrating non-pinned IRQs and tasks to other CPUS and
marking the CPU as not available to the scheduler and load balancer.
Pinned tasks and IRQs are still allowed to run but it is expected that
this would be minimal.
Unisolation works by just marking the CPU available for scheduler and
load balancer.
Change-Id: I0bbddb56238c2958c5987877c5bfc3e79afa67cc
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Open up interface to allow external subsystem to enable and disable hard
lockup detector.
Change-Id: I88a728ee1d54aaa887fab52e5e40d1d4e4fc69ca
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Ensure watchdog does not wake up isolated cpu.
Change-Id: Ie4c6cb1496ae3490d81681f1ad51c8103caa0014
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Add bitmask and corresponding supporting functions for cpu isolation.
Change-Id: Ice1a9503666a2b720bdb324289ca55ceb33097cd
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Do not require CPUSETS to be enabled to allow migration of timers and
hrtimers.
Change-Id: Ib911a0d34c250c4df020bdb265b92d2b8df8db93
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Add function to migrate timer that will be used by later patch set.
Change-Id: I370e404001344e635a663822b07557abbe0f6f52
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Updated commit text and fixed trivial merge conflict]
Git-commit: 3633b88d8fcb4273807574c27c328b6908a741e5
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
An hrtimer may be pinned to a CPU but inactive, so it is no longer valid
to test the hrtimer.state struct member as having no bits set when inactive.
Changed the test function to mask out the HRTIMER_STATE_PINNED bit when
checking for inactive state.
Change-Id: I632f37874ef79887ee1202a028ef734f392d6ed0
Signed-off-by: Gary S. Robertson <gary.robertson@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: 902e4d4eb0d2158d2792166221a72a829caecf07
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
To isolate CPUs (isolate from hrtimers) from sysfs using cpusets, we need some
support from the hrtimer core. i.e. A routine hrtimer_quiesce_cpu() which would
migrate away all the unpinned hrtimers, but shouldn't touch the pinned ones.
This patch creates this routine.
Change-Id: I51259ea41e3bd5cdba50b718201a6840174a7224
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: d4d50a0ddc35e58ee95137ba4d14e74fea8b682f
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
'Pinned' information would be required in migrate_hrtimers() now, as we can
migrate non-pinned timers away without a hotplug (i.e. with cpuset.quiesce). And
so we may need to identify pinned timers now, as we can't migrate them.
This patch reuses the timer->state variable for setting this flag as there were
enough number of free bits available in this variable. And there is no point
increasing size of this struct by adding another field.
Change-Id: If3b3770e547971809e789ea7c8033c48ec2aa92d
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: 62feaf1ed0b64c04868d143d8bdb92d60dc3189b
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
To isolate CPUs (isolate from timers) from sysfs using cpusets, we need some
support from the timer core. i.e. A routine timer_quiesce_cpu() which would
migrates away all the unpinned timers, but shouldn't touch the pinned ones.
This patch creates this routine.
Change-Id: I8624e0659b86b7b8fa425a3fafdb0784fe005124
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4. Fixes for compilation error]
Git-commit: 313910b70ea0c73f8789d9189c11e1f339080646
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
This is needed to support migration of timers during cpu isolation. A
timer might be running on the CPU that we want to isolate so we are
unable to migrate the timers at this point. We are adding a spin-loop to
wait for the timer to finish before migrating the timers.
Change-Id: I24d6e91b6dff468c640c2fe3a37a7f31b6f0c79a
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
